<!DOCTYPE html>
<title>Tests mouse interactions on a non-custom composited root scrollbar thumb.</title>
<script src="../../../resources/testharness.js"></script>
<script src="../../../resources/testharnessreport.js"></script>
<script src="../../../resources/gesture-util.js"></script>
<script src="../../../resources/scrollbar-util.js"></script>
<body style="height: 1000px; width: 1000px">
<script>
window.onload = () => {
  const TRACK_WIDTH = calculateScrollbarThickness();
  const BUTTON_WIDTH = TRACK_WIDTH;

  promise_test (async () => {
    if(navigator.userAgent.includes("Mac OS X"))
      return;

    await waitForCompositorCommit();
    resetScrollOffset(document.scrollingElement);

    // Testing the vertical scrollbar thumb with touch.
    let x = window.innerWidth - TRACK_WIDTH / 2;
    let y = BUTTON_WIDTH + 10;

    let drag = {
      start_x: x,
      start_y: y,
      end_x: x,
      end_y: y + 100
    }

    const scrollPromise = waitForScrollEvent(document);
    await touchDragTo(drag);
    await scrollPromise;
    await waitForCompositorCommit();

    // The compositor thread ingests touch moves and we do not account for the
    // slop region in ScrollbarController. The browser process conversely
    // does subtract the slop region from the scrollbar thumb delta, therefore
    // scrollY would be less by a value of slop region * scroller_to_scrollbar_ratio
    assert_approx_equals(window.scrollY, 183, 28, "Touch dragging scrollbar did not scroll right amount");

    // Since the horizontal scrolling is essentially the same codepath as vertical,
    // this need not be tested in the interest of making the test run faster.
  }, "Test touch drags on non-custom composited root scrollbar thumb.");
}
</script>
</body>
